I ran standard M-sport suspension on my E91, then replaced with Koni yellow sports and Eibach springs, and adjusting to midway damping position found them to be way, way more comfortable than the M-sport stuff.

Infact, for me, the suspension was too soft, so have replaced with Ohlins DFV, custom spring rates (350/700), uprated anti-roll bars and all M3 replacement arms and bushes. The ride is now far more controlled, not harsh or hard, but has an extremely controlled and quality feel about it. Far nicer than stock.